The rich tourists whose luxury yachts once crowded the idyllic Marina Hemingway complex on the outskirts of the Cuban capital are shocked to find all Havana's hotel rooms fully booked until mid-2006. More than a dozen hotels have been temporarily closed to tourists to make way for a different kind of visitor. Most of them arrive nearly blind; but all will be able to see perfectly before they leave.

A remarkable humanitarian programme is under way here, which aims to restore the sight of six million people through free eye surgery. Launched in July by the 79-year-old Cuban President, Fidel Castro, and Venezuela's Socialist leader, President Hugo Chavez, Operation Miracle has brought daily planeloads of the poor from across Latin America and the Caribbean to Havana for surgery. Cuba provides the medical skills, Venezuela the petro-dollars.

People suffering from cataracts and other eye conditions that can be quickly remedied are candidates.

Cuba's comprehensive, free healthcare system has a ratio of one doctor for every 170 Cubans, compared with 188 in the US and 250 in the UK.